This sensitive bio-monitoring circuit was found in the December 1984 issue of Radio Electronics magazine. The circuit is powered by a 9 V battery and uses a low-impedance headphone output.
When this circuit is activated the LED flashes for a moment indicating that the function has been...
This is the basic configuration for using a moving bar indicator or bargraph using the LM3914...
This circuit was found in old documentation. Transistors can be general purpose JFET types and the...